JGF Proposed FP Execution Modes
Language Chip Architecture
Modifier x86 PowerPC SPARC
strictfp Java 1.0 (no double Java 1.0 Java 1.0
rounding on underflow) (no fused mac)
default i.e. larger exponent range fused mac can Java 1.0
no modifier allowed be used
associativefp many optimizations allowed on all platforms
- Current default is essentially strictfp although not always implemented precisely
- mac is fused hardware multiply-add (a*b+c)
- strictfp is a little more than 2 times slower than default on INTEL x86 for a vector dot product